Measuring apparatus



March 13, 1945. s. T. LESTER MBASURING APPARATUS mi NQ Filed June 5,1942 \o nl Patented Mar. 13, 1945 fi'iavf UNITED i STATES PATENT OFFICEMEASURING APPARATUS Stephen T. Lester, Cleveland Heights, OhioApplication June 5, 1942, Serial No. 445,876

Claims. V(o1. as me) t This invention relates to measuring apparatus andparticularly to apparatus intended for the extremely accuratemeasurement or gaging of articles.

An object of the invention is to provide an improved measuring.'apparatus with which any of a large number of measurements may beobtained with extreme accuracy.

Another object is to provide an improved meas.` uring apparatus whichmay easily be arranged to provide any desired measurement.

Another object is to provide an improved measuring apparatus which willconsist of few and simple parts. v

Another object is to provide an improved measuring apparatus which will`besmall and may easily be handled.

Another object is to provide an improved measuring apparatus which willnot be affected by handling. i

Another object is to provide animproved measuring apparatus in whichmaximum number of measurements may be obtained with a minimum number ofparts.`

Another object is to provide an improved measuring apparatus in whichall the parts will be of substantial s'ize and therefore convenient inmanufacturing and handling.

Another object is to provide an improved measuring apparatus in whichthe accuracy isvdependent on the parts chosen, rather than uponadjustments. I

Another object is to provide an improved measuring device in whichanadjustable measuring device may readily be associated with anextension providing a predetermined and extremely accurate base reading.

Another object is to provide an improved measuring device which may beprovided with an extension which may readily be adjusted to any` of aplurality of extremely accurate base readings.

Other objects will hereinafter appear.

Figure 1 isv a side elevational view of an assembled gage embodying thepresent invention;

4Figure 2| isa longitudinal sectional view taken on the line II--II of.Figure 1;

Figure 3 is a transverse sectional view taken on the line III-III ofFigure 2;

lFigure 4 is a disassembled view, parts being broken away and shown insection,- of some of the components of Figures 1 to 3; and

Figure 5 is a fragmentaryelevational view of an adjustable measuringdevice associated with parts disclosed in the preceding gures.

This application is a continuation, in part, of my former application,Serial Number 234,665, led October 12, 1938.

In the measuring apparatus disclosed, very accurate measurements areobtained by the use of a series of gage blocks having parallel plane endsurfaces which are carefully andaccurately finished, as by being lappedor otherwise, so that these surfaces not only conform very closely totrue theoretical planes in exact parallelism, but are at very accuratelydetermined distances.

In practice, these surfaces so nearly conform to a true theoreticalplane that the gage blocks may be secured together by being wrungtogether, that ls, by the surfaces of adjacent blocks being slidlaterally upon each other to exclude any air from between theirsurfaces, so that atmospheric pressure on the other parts of the blocksholds them together.

In Figures 2 and 3 of the drawing, two gage blocks I and 2 havingparallel plane end surfaces are illustrated, these blocks being ofcylindrical shape with their plane surfacesnormal to the axes of thecylinders.

In addition to the blocks having opposed plane end surfaces, there areillustrated two end blocks 3 and 4, each of which has one plane endsurface 5 and at its opposite end is lprovided with a contacting anvil6. The Vend surfaces of these anvils may be plane or convex, and arespaced at predetermined distances from the' surfaces 5 of the endblocks.

For adjustment, the anvils are threaded, as indicatedat 1, into the endblocks, being secured in Jadjusted position by lock screws or threadedplugs 8, likewise threaded into the axial openings through the endblocks. It will be apparent that, by backing off thelock screw 8, theanvil 6 may be simply adjusted by turning the same' relative the block,and it then may be easily locked ,in its newly adjusted position bytightening the lock screw tightly against its end.

Theblocks intermediate the end blocks will hereinafter be referred to ascylindrical blocks, because there is no need of varying their crosssectional shape through their extent. Although these blocks have beenshown as circular in cross section, it will beunderstood that theymight, if desired, be elliptical cylinders, or of prismatic shape, orother forms, but the circular form shown is one of the most convenientand is the one which is now being used exclusively.

It will be also understood that the blocks I to 4 are only part of aseries which may compre- 'hend as many blocks as desired, which may beof identical lengths, or different lengths in any desired series ofincrements.

For instance; a series of fteen blocks each of a, length of one-inchmight be used, or a series of four blocks comprising one of a length ofone one-inch, one of two-inch length, one of fourinch, and one ofeight-inch will permit arrangements of blocks giving measurement byone-inch intervals from one to fteen inches.

If halfinchinteryals are desired, .theabove set need be augmentedby onlya single`-half.n`ch block.

For another example; with only ve end blocks and thirty-threecylindrical blocks, I can obtain all measurements from 2.4005 inchesupwardly Ato twenty-two inches inclusive, insteps of ..00025 inch. Theblocks constituting this set comprise two end blocks eachmeasuring.exactlyrloneiinch in length, a third end block measuring .995'inch, a fourth of 1.0025 inches, and a fth of 1.005

inches.

"The cylindrical blocks of this set are-most; simply considered asdivided .into fournseries. 'Ihe yIirst of these 1series* includes`nine-blocks ygwhich,

measured across :theirplanef' end surfaces, are in length, respectively,;.l00,` .200,-.300,--.40,0, .500, '.600, .700,;.80 0, and .900:inch. l

The: second' seriesconsists of :ninermore blocks, measuring,respectively, across'- their planes-surfaces 5.201, .202, 8.203,r .204,.205, 1206.120?, T208, and .209 inch.

`The third series consists of :anotherinine: blocks, ofthe :respective.lengths'of .:.210,..220, .230, .1.240, .250, .1.260, .270;.280,.and-290 linch.

lThe remaining Iseries :consists fof,..six.-b 1ock which measure,respectively,-` one, two,- thre.e;ffour, five, and six inches.

If, for example, it isdesired.-.vvithvthis set-oi blocks to measure adistancesof.5.606.75:inches;;it

isonly necessary to assemble the lendlblocksimeas-Y uring .9995 and.1.00025;in'chesiwth'..theuthree inch lblock, :the 5400 in'chblockand the::.207'.inch block.

If a quarter of a thousandth-.more is required, the ,1,0005v inch end.lblock; :is :substituted;;fo-r 1.00025iinch. '.Ifaquartenoiathousandth:less is desired, Ione of the yone linch .blocks`is; substituted for` the 1.00025 inch,-.so-that2it twill be, apparentthatdimensions in quite.=odd decimal fractions: may readilybe:obtainedrfwithtthisasmall number of blocks. l

It is also apparent that no blc1c1ris.'less` :than

.'100 inch in thickness :andfonlypne `i'stlessgithan .200inch, so thatall are large' enougrrfor-,con-

vement-handling.

`Whilethe blocks -could berusedalone, :merely beingheld together byatmospheriopressure, considerable caremust-'be exercisedinhusing .themin this manner, as ithey-mayi-be ljarredf` apart; or subjected totemperature Variations when-:heldin vthe hand, and in generah areAexposed Aliowear, dirt, `moisture, and the like-#and it khasalz'eenfound desirable to assist the atmosphericpressure by providing aprotecting arid vhandling covering, preferably onewhichis ycomposedonalnommagnetic material-Which is also an-vinsulatorvagainst both heatand electricitv-suchf'for linstanceas hard rubber, moldedplasticgvulcanizedlber;.and the like. i, v

This covering consists or a series of sleevesrs, I and II, which' are'slotted lengthwise, asoindicated at,` l2, ltopermitthe'-edges-tohbefsomee what sprungv apart on-being 'pula overfthevvlololcks, so that the 'sleeves *Will-'nt tightly oven-the same. Toassist` lin ythis'gripping\actiong'eachsleeve is shown as being formedwith one or more annular recesses I3, in which recesses are positionedsmall circular Wire springs I4 which tend to contract the sleeves andaugment their gripping action.

The slotted sleeves are, in turn, surrounded by two telescopic tubularmembers I5 and I6.

The outer end of the outer tubular member I5 is slotted as indicated atI'I, at the end which embraces theinner tubular. member` 1.6,. andexft'erio'rlyl of:.this,slotted portion is Aprovided with a taperedthread engaging the conjugate internal thread of a cylindrical ring I8,so that by tightening the ring I8 upon the threads of tubular -member.45, the furcations of the latter are V4clamped `.tightly-upon theexterior of tubular 'member |6.

' ternallyvthreadcd cap;or;.fplug-20, eachcapaor plug having a centralaperture through which .the .anvilf' lof theadjacent end blockvmaywpro-`ject. y l f l 'The device .is assembled-as follows:

After the blocks aggregating any, desired length have ',beencchosen, lthese rare "wrung .together and..surrounded.by la suflicient numberoffslot ted sleeves (suchasp9to Il)so that'thesesleevesoverlie-eachjunction -between theend surfaces o1' successive blocks.

The blocks and slotted sleeves are'than'slid within. the; tubular.member` I6 which; looselyengages? the exteriorsofithe slotted sleeves,the tubular member I5 is then slid over the'exposedend ofthe-series ofblocks:thetubularmembers I5 and librought Aas tight1y..together yasconveniently may be done by hand, and the ring I8 tightenedfuponithe.threads .to'clamp these: tubular members together.

'If additional. vpressure 'is r.desired upon the ends of theend blocks,one or both of the caps 20 may betightened within its threads at theendfof its tubular member.

lIna 1sense, the vconnection I between .the tubular members constitutesla coarse clampingadjustment, and theadjustment of theplugs .or capsaffiner clamping adjustment.

With the 4bloclrsVslotted sleeves, andftelescopic tubular membersassembled as aboveoutlined, the blocks :are well .protected andAinsulated vagainst heat -or- `electricity 'al-...all points, exceptingthe two exposed-anvils v"l, and the idevice vmay be' jarredordroppedllwithout. fdisplacingthev blocks and isl to all intents andpurposes as. unitaryzas .Wouldbea single purposelgage, made to thelength t0 rwhich it vhas been set. y.

jIt is no=more bulky-nor lheavy than the conventional single-piece/ gagefor asinglexmeasurement, and its accuracy is at least the equivalent ofany other:measuring standard; such as kthe more cumbersome vrectangularyblocks now :in

vogue.

Howeven .whenitrisgdesired to change the .gage to a different size, fitscomparatively fewparts maylbe quickly and :easily disassembled,.vandthe.

gage shortened o1' :lengthened 1 by removal, insertion, orinterchangeofblocks, even for 4such small :graduations that it may be,quickly changedover to usejor .goi and then for nego gaging.

. In Figuren-aan internal. micrometer head, `indicatedgenerallyatqzl,has 1been attached to the anvil 6 crane-'ot theyblocks of; the gage.described in the previous figures. The micrometer head is shown in thedrawing as attached to the anvil by means of set screws 23 and; 24having knurled heads by which they may be moved manually.

This head. it will be understood, is adjusted so that the end of itsanvil 22 is, when the head is set to zero reading, a predetermineddistance from surface 5 of the end block, as, for instance, an evennumber of inches..

With this micrometer head or similar measuring device applied to theanvil, it will be apparent that adjustments within the range of themeasuring device may readily be made without disassembling the device orchanging the blocks, and that no blocks of dimensions within the rangeof the measuring device need be used. In other words, with a one inchmicrometer head, blocks in multiples of one inch in length may be used,and all intermediate measurements obtained by adjustment of the head.This, of course, converts thegage into a simple, highly accurate andvery efllcient internal micrometer.

While I have described the illustrated embodiment of my invention insome particularity, obviously many others will readily occur to thoseskilled in this art, andI do not, therefore, limit myself to the precisedetails shown and described,

but claim as my invention all embodiments, variations, and modificationsthereof coming within the scope of the appended claims.

, scoped position.

2. A gage comprising a series of measuring blocks having accuratelyformed parallel surfaces at predetermined distances, a holder for saidblockscomprising two telescopically arranged .hollow members havingopenings at the ends tion, the remote ends of the telescopic membersbeing threaded, and threaded perforated mem bers engaging said threads,aV portion of the end blocks being capable of extending through theperforations of said members.

4. A measuring device comprising a plurality of cylindrical blockshaving parallel plane end surfaces at predetermined distances, a slitresilient sleeve frictiorially engaging the cylindrical surface of saidblocks, and a cover consisting of two relatively adjustable telescopicparts surrounding said blocks and sleeve.

' 5. A gage comprising a plurality of cylindrical blocks each havingparallel plane end surfaces at a predetermined distance, the blocksbeing secured together axially by the bringing in contact of the planeend surfaces of successive blocks and `excluding air from the spacebetween said snrfaces, and a cylindrical sleeve slidable axially overthe assembled blocks and holding said blocks from radial displacementrelative each other, said sleeve being composed of heat insulatingmaterial, projecting contacting tips on the end blocks of the series,and pressure applying means engaging said end blocks and retaining thesleeves against axial movement beyond the series of blocks.

STEPHEN T. LESTER.

